System and method for preparing hypochlorous acid disinfectant

Abstract

The invention relates to a system for preparing a disinfectant, comprising:-a dilution tank (300) provided with a water inlet (302) for injecting water; -an electrolysis device (100) arranged below the dilution tank (300) and comprising:-an electrolysis reaction chamber (110) for storing a solid alkali metal chloride,-a set of electrodes (120),-a conduit (200) for connecting the electrolysis reaction chamber and the dilution tank, in which:-water is injected into the electrolysis reaction chamber synchronously through the conduit in order to dissolve a portion of the solid alkali metal chloride while injecting water into the dilution tank,-the electrolysis reaction chamber (110) is separated from the dilution tank (300); and-electrolyzing the aqueous solution in the electrolytic reaction chamber to produce hypochlorous acid, at least part of the hypochlorous acid being migrated from the electrolytic reaction chamber to the dilution tank via the conduit, the migrated at least part of the hypochlorous acid being mixed and diluted with the water in the dilution tank to form the disinfectant.

Description

Technical Field

[0001] The present invention relates to a system for preparing hypochlorous acid disinfectant solution. The present invention also relates to a method of using such a system.

[0002] The present invention belongs to the field of manufacturing and designing hypochlorous acid electro-chemical production equipment and systems. The present invention is particularly applicable to the field of disinfection, such as but not limited to the disinfection of water, air, hard or soft surfaces, animal or plant or human surfaces, and medical equipment surfaces. Background Art

[0003] Hypochlorous acid (CAS No.: 7790-92-3) is a weak inorganic acid with the chemical formula HClO. It dissociates partially in water to form hypochlorite ions (ClO - ), as shown in Chemical Reaction Equation 1:

[0004]

[0005] As Figure 1 shown, the distribution ratio of the two chlorine species (HClO / ClO - ) in an aqueous solution depends on the pH value of the water.

[0006] As Figure 1 can be seen, when pH < 7.6, hypochlorous acid is the dominant form; when pH > 7.6 (alkaline), hypochlorite is the dominant form. When the pH value is below 3.5, chlorine gas begins to form. In order to maintain the morphological stability of the hypochlorous acid (HClO) solution, maximize its antibacterial activity, and minimize the formation of adverse by-products, the pH value should preferably be maintained between 3.5 and 7.5.

[0007] In addition, hypochlorous acid (HClO) is a key bactericidal component in the innate immune system, naturally secreted by mammalian white blood cells to resist infection. It has the property of killing a broad spectrum of microorganisms (bacteria, viruses, fungi, etc.). Compared with the commonly used disinfectant sodium hypochlorite (the main component of bleach water), the bactericidal efficiency of hypochlorous acid is 80 to 120 times higher, and it is less irritating to the skin.

[0008] The application fields of hypochlorous acid include water treatment, food hygiene and safety, cleaning and disinfection of various surfaces, objects or foods, as well as pharmaceutical and medical applications, especially in wound care and skin disinfection. It should be noted that the U.S. Food and Drug Administration (FDA) has approved the use of hypochlorous acid as a biocide. In addition, the European Commission approved the use of active chlorine released from hypochlorous acid (EC number: 232-232-5) as an active ingredient in biocide products for human hygiene in July 2021. The outbreak of the novel coronavirus (Covid-19) in recent years has led to a shortage of alcohol-containing disinfectant products in the market on the one hand, and on the other hand, it has also proved that hypochlorous acid plays an important disinfection role in high-risk areas of Covid-19 infection. Therefore, the demand for hypochlorous acid disinfectant solutions is increasing in many current application fields (such as water treatment, agro-food, cosmetics, pharmaceuticals, etc.).

[0009] In the prior art, various systems and methods for preparing hypochlorous acid disinfectant solutions have been proposed. For example, these known systems and methods include:

[0010] - The chlorine hydrolysis method as shown in Reaction Equation 2 below,

[0011] - The hypochlorite ion acidification method as shown in Reaction Equation 3 below,

[0012] - The electrolysis method of aqueous sodium chloride solution as shown in Reaction Equations 4-6 below.

[0013]

[0014] 2Cl - (aq) →Cl2(g)+2e - (4)

[0015] 2H2O (l) +2e - →H2(g)+2OH - (aq) (5)

[0016] Cl 2(g) +2OH - (aq) →OCl -(aq) +Cl - (aq) +H2O (l) (6)

[0017] Although the method shown in Reaction Equation 2 can quickly and efficiently prepare hypochlorous acid disinfectant solution, its practical application is very limited due to the inherent risks of chlorine treatment and its storage hazards.

[0018] The method shown in Reaction 3 prepares hypochlorous acid disinfectant by acidifying an aqueous solution of hypochlorite (such as calcium hypochlorite or sodium hypochlorite) with an acidifying agent (such as hydrochloric acid). However, this method requires precise control of the pH value and temperature during the acidification process to prevent or reduce the generation of toxic chlorine gas. Additionally, this method requires the preparation, transportation, and storage of hypochlorite and acidic products, both of which are corrosive chemicals.

[0019] The method shown in Reactions 4 - 6 is the most widely used method for preparing hypochlorous acid disinfectant. This method generally only requires adding an alkali metal chloride (such as sodium chloride or potassium chloride) to water, without the need for other chemicals. The specific steps of this method are as follows: Inject an aqueous solution containing a certain proportion of alkali metal chloride (such as sodium chloride) into a container or reaction chamber equipped with an electrolytic cell, which includes at least one anode and at least one cathode; electrolyze this aqueous solution to generate an aqueous solution of hypochlorous acid; transfer this aqueous solution of hypochlorous acid to another reaction chamber or container, for example, by pumping, and dilute it with water to obtain hypochlorous acid disinfectant. It should be noted that Reaction 4 (chloride ion oxidation reaction) occurs at at least one anode, thereby generating chlorine gas; while Reaction 5 (water reduction reaction) occurs at at least one cathode, thereby generating hydrogen gas.

[0020] It should be noted that the electrolytic cells involved in the existing methods are divided into the following two categories:

[0021] - The first category is a divided electrolytic cell, which uses a diaphragm to completely isolate the anode products and cathode products in the cell. Therefore, the chlorine gas generated by the anode according to the reaction formula dissolves in water, and then hypochlorous acid is generated through Reaction 2 described above;

[0022] - The second category is an undivided electrolytic cell, which does not use a diaphragm; in this case, the chlorine gas generated by each anode can directly react with the hydroxide ions generated by each cathode to generate hypochlorite ions through Reaction 6; and this hypochlorite ion can form a dynamic equilibrium with hypochlorous acid according to Reaction 1 described above.

[0023] The electrolysis methods and systems in the prior art all have one or more of the following disadvantages:

[0024] - The disinfectant produced is usually contaminated by a large amount of chloride salts, and / or has too high a dilution ratio, and / or has a low concentration of hypochlorous acid (<3 ppm);

[0025] - Usually relies on large - scale equipment, and / or has a high process complexity, so the cost is high;

[0026] - It is impossible to adjust the concentration of hypochlorous acid as expected during the production of the disinfectant, so it cannot meet the user's needs. As described above, the disinfectant has a wide range of applications, so it is necessary to ensure that users can choose the most suitable concentration of hypochlorous acid according to the specific disinfection operation requirements.

[0027] The present invention aims to solve all or part of the above-mentioned drawbacks existing in the prior art. Another object of the present invention is to provide a system or method for preparing hypochlorous acid disinfectant solution so that users can obtain a disinfectant solution with a hypochlorous acid concentration most suitable for their intended use. Another object of the present invention is to provide a system or method with a simple design, easy to implement, easy to operate, suitable for large-scale and small-scale production, and low cost. Another object of the present invention is to provide a system or method that allows users to efficiently monitor the preparation of the disinfectant solution. Summary of the Invention

[0028] The solution proposed by the present invention is a system for preparing hypochlorous acid disinfectant solution. The remarkable feature of the system is that it includes:

[0029] - A dilution tank dedicated to preparing the disinfectant solution, which is provided with a water inlet for injecting water into it;

[0030] - At least one electrolysis device, which is arranged below the dilution tank and includes:

[0031] -- An electrolysis reaction chamber for storing solid alkali metal chloride,

[0032] -- At least one electrode group including at least one anode and at least one cathode, which is arranged in the electrolysis reaction chamber,

[0033] -- A conduit for realizing fluid communication between the electrolysis reaction chamber and the dilution tank.

[0034] Another remarkable feature of the system is that the conduit is arranged such that when water is injected into the dilution tank, water is simultaneously injected into the electrolysis reaction chamber to dissolve part of the solid alkali metal chloride stored in the electrolysis reaction chamber, thereby forming an aqueous solution containing chloride ions; and when the aqueous solution in the electrolysis reaction chamber is electrolyzed by the electrode group to generate hypochlorous acid, at least part of the hypochlorous acid can migrate from the electrolysis reaction chamber to the dilution tank and be mixed and diluted with the water therein to form the disinfectant solution.

[0035] The preparation system of the hypochlorous acid disinfectant solution described in the present invention has many advantages, including simple design, easy implementation, suitability for large-scale and small-scale production, and low cost. In addition, the system described in the present invention can ensure that users obtain a disinfectant solution with a hypochlorous acid concentration most suitable for their intended use. In fact, users can adjust the system to control the expected content of free chlorine (for example: 5 ppm, 100 ppm, 250 ppm, 1500 ppm, 3000 ppm or more than 3000 ppm), so as to prepare a disinfectant solution with the required hypochlorous acid concentration. To this end, users can adjust the system in various ways, for example, increasing the number of electrolysis devices, and / or the number of electrode groups in each electrolysis device, and / or the number of electrodes in each electrode group. It should be noted that the system described in the present invention does not include any transfer devices, such as pump transfer devices, so the hypochlorous acid (and / or hypochlorite ions) generated in the electrolysis reaction chamber cannot be transferred from the electrolysis reaction chamber to the dilution tank through such transfer devices to be mixed with water to form a disinfectant solution. It should also be noted that only water is stored in the dilution tank arranged above the electrolysis reaction chamber before electrolysis, and after electrolysis, the water is replaced by a disinfectant solution.

[0036] Other beneficial features of the present invention are listed as follows. Each of the features described can be applied independently, or in combination with the aforementioned significant features, and one or more divisional patent applications can also be filed according to specific circumstances:

[0037] Preferably, by adjusting the electrolysis of the aqueous solution in the electrolysis reaction chamber, bubbles are generated, and the bubbles generate turbulence, and the turbulence can force at least part of the hypochlorous acid to migrate from the electrolysis reaction chamber to the dilution tank through the conduit.

[0038] The at least one electrolysis device can be one, two, three or more than three electrolysis devices.

[0039] The at least one electrode group can be one, two or more than two electrode groups.

[0040] Preferably, the at least one electrode group further includes a plurality of bipolar electrodes, and the plurality of bipolar electrodes are interspersed between the anode and the cathode of the at least one electrode group.

[0041] More preferably, the at least one anode, the at least one cathode and the plurality of bipolar electrodes of the at least one electrode group are all in the shape of flat plates arranged parallel to each other and at equal intervals.

[0042] In an alternative embodiment, the at least one electrode group includes a plurality of anodes and a plurality of cathodes, and the plurality of anodes and the plurality of cathodes are in the shape of flat plates arranged in parallel with alternating polarities.

[0043] The electrolysis reaction chamber of the at least one electrolysis device has a capacity of at least 10 liters.

[0044] The dilution tank may further include a bubble breaking device for breaking (or reducing the size of) chlorine gas bubbles that may be generated in the electrolysis reaction chamber of the at least one electrolysis device, thereby promoting the dissolution of chlorine gas in water; the bubble breaking device is arranged at the bottom of the dilution tank and is at least flush with the conduit for realizing fluid communication between the electrolysis reaction chamber and the dilution tank.

[0045] The bubble breaking device may be composed of at least one perforated plate, and the diameter of the perforations is sufficient to reduce the bubbles to a size that promotes the dissolution of chlorine gas in water.

[0046] Preferably, the diameter of the perforations of the at least one plate is less than 5 mm, preferably less than 1 mm.

[0047] Specifically, the bubble breaking device is composed of multiple perforated plates, and the multiple plates are stacked and arranged such that the perforations of two adjacent plates are staggered with each other.

[0048] Preferably, the system of the present invention further includes a measuring device, and the measuring device includes:

[0049] - a sensor for measuring the free chlorine content in the disinfectant solution prepared in the dilution tank,

[0050] - a display for displaying the free chlorine content measured by the sensor.

[0051] Generally, the system of the present invention further includes an adjusting device for adjusting the pH value of the disinfectant solution prepared in the dilution tank.

[0052] Advantageously, the system of the present invention further includes a control unit, the control unit is operably connected to the measuring device for measuring the free chlorine content, and the control unit is used to perform the following operations: comparing the free chlorine content measured by the sensor with a free chlorine content threshold value, and interrupting the electrolysis when the free chlorine content measured by the sensor is equal to or higher than the free chlorine content threshold value.

[0053] Specifically, the free chlorine content threshold value is set to the maximum value selected from the range of 5 ppm to 3000 ppm, especially the range of 10 ppm to 1500 ppm.

[0054] In practical applications, the dilution tank is provided with a water inlet, the water inlet is connected to a water source via a water supply circuit, and a solenoid valve and a circulation pump are sequentially arranged along the direction of the dilution tank in the water supply circuit.

[0055] In practical applications, the dilution tank is further provided with a sampling outlet for sampling the disinfectant solution. The sampling outlet is connected to a tapping point, and the tapping point is located between the solenoid valve and the circulation pump in the water supply circuit, such that the sampling pipeline forms a recirculation loop with the circulation pump and a part of the water supply circuit behind the circulation pump. The recirculation loop is used to circulate the disinfectant solution from the sampling outlet back to the water inlet.

[0056] Preferably, the measuring device for measuring the free chlorine content is located on the recirculation loop, specifically on the sampling pipeline, to ensure continuous measurement of the disinfectant solution.

[0057] The pH value of the aqueous solution to be electrolyzed can be 3 to 8, preferably 6 to 8.

[0058] According to another aspect, the present invention relates to a method for preparing hypochlorous acid disinfectant solution. The remarkable feature of the method is that it includes the following steps:

[0059] a) Provide the system of the present invention;

[0060] b) Inject water into the dilution tank of the system. When injecting water into the dilution tank, water is simultaneously injected into the electrolysis reaction chamber of at least one electrolysis device of the system through the conduit for realizing fluid communication between the electrolysis reaction chamber and the dilution tank, so as to dissolve part of the alkali metal chloride stored in the electrolysis reaction chamber, thereby forming an aqueous solution containing chloride ions;

[0061] c) Apply current to the electrodes of at least one electrode group of at least one electrolysis device to electrolyze the aqueous solution containing chloride ions in the electrolysis reaction chamber, thereby generating hypochlorous acid. Wherein, at least part of the hypochlorous acid migrates from the electrolysis reaction chamber to the dilution tank through the conduit and is mixed and diluted with the water in the dilution tank to form the disinfectant solution;

[0062] d) Measure the free chlorine content of the disinfectant solution prepared in the dilution tank;

[0063] e) When the free chlorine content measured in step d) reaches the expected free chlorine content value of the disinfectant solution, interrupt the electrolysis;

[0064] f) Optionally, measure the free chlorine content of the disinfectant solution prepared in the dilution tank through the sensor;

[0065] g) Optionally, the operation of interrupting the electrolysis in step e) is performed by the control unit, which is configured to compare the free chlorine content measured by the sensor in step f) with the free chlorine content threshold, and interrupt the electrolysis when the free chlorine content measured by the sensor is equal to or higher than the free chlorine content threshold;

[0066] h) Optionally, at least one intrinsic parameter of the disinfectant solution prepared in the dilution tank is measured, and the intrinsic parameter is selected from the list of pH value, temperature, conductivity, and hardness parameter;

[0067] i) Optionally, the pH value of the disinfectant solution prepared in the dilution tank is adjusted.

[0068] In a specific embodiment, the voltage applied to the electrode in step c) ranges from 1 volt to 15 volts, preferably from 2 volts to 10 volts.

[0069] Preferably, the pH value range of the hypochlorous acid disinfectant solution is about 5.1 to 6.9, preferably 6.5.

[0070] Preferably, in the optional step g), the free chlorine content threshold is set to the maximum value selected from the range of 5 ppm to 3000 ppm, especially the range of 10 ppm to 1500 ppm. Description of the Drawings

[0071] Other advantages and features of the present invention will be presented more clearly through the following description of the preferred embodiments in conjunction with the drawings; the drawings are only used to illustrate the embodiments of the present invention by way of example, rather than to limit it, where:

[0072] Figure 1 Shows the dissociation curve of hypochlorous acid in water with the change of pH value;

[0073] Figure 2 Is a schematic diagram of a system for preparing a disinfectant solution according to the present invention, which is equipped with a dilution tank and an electrolysis device;

[0074] Figure 3 Is a schematic diagram of another system for preparing a disinfectant solution according to the present invention, which is equipped with a dilution tank and two electrolysis devices;

[0075] Figure 4 Is a schematic diagram of another system for preparing a disinfectant solution according to the present invention, which is equipped with a dilution tank and three electrolysis devices;

[0076] Figure 5 Is a perspective view of an exemplary electrolysis device according to the present invention;

[0077] Figure 6 Is a perspective view of an exemplary hollow tube used as a support element for an electrode group in the system according to the present invention;

[0078] Figure 7 Is a perspective view of an exemplary electrode group suitable for the present invention;

[0079] Figure 8 Is Figure 2 Schematic diagram of the system shown further equipped with a free chlorine content measuring device;

[0080] Figure 9 Is Figure 8 Schematic diagram of the system shown further equipped with a control unit;

[0081] Figure 10 Is Figure 9 Schematic diagram of an alternative embodiment of the system shown, the system further equipped with a recirculation loop and a dilution tank provided with a liquid level detector;

[0082] Figure 11 Is Figure 9 Schematic diagram of another alternative embodiment of the system shown, the system further equipped with a different form of recirculation loop and a dilution tank provided with a liquid level detector; and

[0083] Figure 12 Is a schematic diagram of an exemplary dilution tank of an alternative embodiment of the system according to the present invention, the dilution tank being provided with a tubular gauge. Detailed Description

[0084] The following is a non - restrictive description. Each feature described in only one embodiment can be extended to other embodiments. Similarly, one or more features described in only one embodiment can be combined with one or more other features described in only another embodiment.

[0085] The following is a non - restrictive description. Each feature described in only one embodiment can be extended to other embodiments. Similarly, one or more features described in only one embodiment can be combined with one or more other features described in only another embodiment. It should be noted that the drawings are highly simplified schematic diagrams, so the proportions between the elements shown therein or between different drawings are not necessarily consistent. The meanings of the reference numerals in different drawings remain the same.

[0086] The present invention mainly relates to a system for preparing hypochlorous acid disinfectant solution. Preferably, the free chlorine content in the hypochlorous acid disinfectant solution is greater than 5 ppm. This system allows users to prepare disinfectant solution on a small - scale, on - site or on - demand, and can also achieve industrial - scale production.

[0087] "ppm" means one part per million. It should be noted that for an aqueous solution, a concentration of 1 ppm can be expressed as follows: 1 ppm = 1 mg / kg ≈ 1 mg / L.

[0088] The system described in the present invention includes:

[0089] - At least one electrolysis device 100, and

[0090] - A dilution tank 300 dedicated to preparing a disinfectant solution.

[0091] "At least one electrolysis device" means one electrolysis device (see Figure 2 ), two electrolysis devices (see Figure 3 ), three electrolysis devices (see Figure 4 ), or more than three electrolysis devices. In addition, for the sake of simplicity of description, hereinafter, only the system equipped with a single electrolysis device as shown in Figure 2 will be taken as an example for illustration, but the system and method described in the present invention can still operate in a similar manner when equipped with two, three or more than three electrolysis devices, and the efficiency of preparing hypochlorous acid and hypochlorous acid disinfectant solution is higher.

[0092] In addition, the electrolysis device 100 adopted includes an electrolysis reaction chamber 110, and the electrolysis reaction chamber is equipped with at least one electrode group 120.

[0093] "At least one electrode group" means one electrode group (for example, see Figure 2 ), two electrode groups or more than two electrode groups (see Figure 5 ). Similarly, for the sake of simplicity of description, hereinafter, only the electrolysis device equipped with a single electrode group as shown in Figure 2 will be taken as an example for illustration, but the system and method described in the present invention can still operate in a similar manner when equipped with two or more than two electrode groups, and the efficiency of preparing hypochlorous acid and hypochlorous acid disinfectant solution is higher.

[0094] On the other hand, as described below, the dilution tank 300 of the system is provided with at least one bottom outlet 303. In principle, each of the at least one bottom outlet 303 is intended to be used in cooperation with an electrolysis device 100. The dilution tank 300 may be provided with two, three or more than three bottom outlets 303, but only one of the bottom outlets 303 is connected to the electrolysis device 100. For example, as shown in Figure 2 , the system described in the present invention is equipped with a single electrolysis device 100, and the dilution tank 300 is provided with a single bottom outlet 303. However, the dilution tank 300 may be provided with a plurality of bottom outlets, and the unused bottom outlets can be closed by appropriate means (for example, plugs, cocks, globe valves).

[0095] Electrolysis device 100

[0096] One or more electrode groups 120 of at least one electrolysis device 100 are respectively powered by an electric current generated by an energy source 101. This electric current can be direct current and / or pulsed current.

[0097] As Figure 2 shown, the electrolysis device 100 includes an electrolysis reaction chamber 110 for storing solid alkali metal chloride, and is usually provided with an upper opening 111, which can be closed by a movable cover plate 130.

[0098] The solid alkali metal chloride stored in the electrolysis reaction chamber 110 is used to be mixed with water in the reaction chamber 110 to generate an aqueous solution containing chloride ions, and hypochlorous acid can be obtained by electrolyzing this aqueous solution.

[0099] In the present invention, "alkali metal chloride" refers to sodium chloride, potassium chloride, and mixtures thereof. For the sake of simplicity of description, only sodium chloride will be taken as an example hereinafter, but the systems and methods described in the present invention are applicable to various alkali metal chlorides.

[0100] In the present invention, "solid state" refers to any solid form with a weight of about 5 grams to 30 grams. Preferably, the solid alkali metal chloride (such as sodium chloride) is selected from grains, tablets, and tablets. The advantages of using solid alkali metal chloride will be discussed hereinafter.

[0101] The reaction chamber 110 can be made of any suitable electrically insulating material that is resistant to corrosion by an aqueous solution containing an alkali metal chloride (such as sodium chloride) and the products generated during the electrolysis process. Preferably, the reaction chamber 110 is made of transparent glass or hard plastic, such as polyvinyl chloride (PVC), glass fiber reinforced polypropylene (PRV), acrylonitrile-butadiene-styrene copolymer (ABS), or polycarbonate (PC). Obviously, the above is not an exhaustive list. Using transparent glass or plastic materials helps to visually inspect the internal components of the reaction chamber 110 and helps to observe the electrolysis reaction in real time during normal operation.

[0102] In practical applications, the reaction chamber 110 has a cylindrical shape with a circular cross-section and extends longitudinally. Its height ranges, for example, from 15 cm to 150 cm, or is higher than 150 cm, and its diameter ranges, for example, from 10 cm to 80 cm, or is greater than 80 cm. The shape and size of the reaction chamber 110 are only for illustrative reference, as the reaction chamber can have any other suitable shape (e.g., parallelepiped or cylindrical with an elliptical cross-section, or other shapes) and size to best fit the intended application scenarios of the electrolytic reaction chamber 110 and the system described in the present invention. In addition, the reaction chamber 110 can adopt all geometric shapes formed by a straight line moving axially parallel and relying on two fixed planes. Therefore, the circular cross-section of the cylindrical reaction chamber can be truncated to form a planar portion 112 that almost covers its entire height, as Figure 5 shown.

[0103] As Figure 2 and Figures 8 to 12 shown, the electrolytic reaction chamber 110 of the system described in the present invention is equipped with an electrode assembly 120 for connecting to an energy source 101 to generate an electric current. It should be noted that the present invention is not limited to this embodiment, and the electrolytic reaction chamber 110 can also be equipped with two, three, or more than three electrode assemblies 120. The number of electrode assemblies 120 configured can be selected according to the expected overall performance (e.g., the production time of hypochlorous acid disinfectant solution). In fact, the applicant has verified that when the system described in the present invention is equipped with a single electrolytic reaction chamber 110, as the number of electrode assemblies increases, the production time of the disinfectant solution with a specific free chlorine content will be shortened. This is highlighted in Example [Table 1], and it demonstrates the influence of the number of electrode assemblies 120 equipped in each electrolytic device 100 on the production time of the disinfectant solution described in the present invention.

[0104] One or more electrode assemblies 120 each include at least one anode and at least one cathode (not shown in the figure). It should be noted that according to the definitions well-known to those skilled in the art, the term "anode" refers to the positive electrode, which is the location where the oxidation reaction shown in the above reaction formula occurs; while the term "cathode" refers to the negative electrode, which is the location where the reduction reaction shown in the above reaction formula occurs.

[0105] (At least one) The electrodes of the electrode assembly 120 can be made of the following materials: titanium, titanium coated with a catalytic coating (including metal oxides such as titanium oxide, ruthenium oxide, iridium oxide, and tin oxide), titanium alloy, (Nickel-chromium-molybdenum alloy) alloy or any other corrosion-resistant metal or alloy. For example, the catalytic coating may consist of 45% to 55% titanium oxide, 25% to 30% ruthenium oxide, and 20% to 20% iridium. The electrode can be in a flat plate shape or other suitable form to best fit the intended application scenario of (at least) one electrode group 120 described in the present invention. Preferably, the electrodes in (at least) one electrode group 120 are in a flat plate shape, and its thickness (e.g., 1 mm to 4 mm) should ensure sufficient hardness. The width range of the flat plate electrode is, for example, 25 mm to 100 mm, and its length is sufficient to radially insert (at least) one electrode group 120 into the reaction chamber 110, so as to ensure that at least the electrodes of one electrode group 120 are at least partially arranged inside the reaction chamber 110. For example, for a reaction chamber with a diameter of 25 cm, the width of the flat plate electrode can be less than 25 cm, and the length range is, for example, between 15 cm and 24 cm. Specifically, the electrode spacing ranges from 0.1 cm to 1.2 cm, preferably from 0.1 cm to 0.5 cm. It should be noted that the smaller the electrode spacing, the larger the contact / reacting surface area per unit volume, and the lower the required voltage. In fact, as the electrode spacing increases, the energy requirement for driving the current through the aqueous solution containing chloride ions (by ionic conduction) also increases. The increase in electrode spacing leads to an increase in resistance, so in order to maintain the same current intensity, the voltage needs to be increased (Ohm's law).

[0106] In a specific embodiment of the present invention (not shown in the figure), (at least) one electrode group 120 includes two electrodes, namely an anode and a cathode. The anode and the cathode are in a flat plate shape parallel to each other, and the spacing is, for example, 0.1 cm to 1.2 cm, preferably 0.1 cm to 0.5 cm.

[0107] In other specific embodiments of the present invention (not shown in the figure), the electrode group 120 may include two or more anodes and two or more cathodes. These anodes and cathodes are in a flat plate shape parallel to each other and are alternately arranged in the electrode group 120. The adjacent electrode spacing is, for example, 0.1 cm to 1.2 cm, preferably 0.1 cm to 0.5 cm.

[0108] Preferably, (at least) one electrode group 120 further includes one or more bipolar electrodes, and the one or more bipolar electrodes are arranged between the anode and the cathode of the electrode group 120.

[0109] In the present invention, the term "bipolar electrode" refers to an electrode with an intermediate potential between a high-potential electrode and a low-potential electrode, such that the part of the electrode facing the low-potential electrode simultaneously acts as an anode, while the part facing the high-potential electrode simultaneously acts as a cathode. For a flat plate electrode, anodic reaction occurs on one side and cathodic reaction occurs on the other side.

[0110] The bipolar electrode can be made of the same corrosion-resistant metal or alloy as the other electrodes of at least one electrode group 120. In addition, the bipolar electrode can also have a geometric shape that is substantially similar to or the same as the anode and cathode of the (at least one) electrode group 120. Preferably, the anode, cathode, and bipolar electrodes are all in the form of flat plates arranged parallel to each other and at equal intervals, with the interval being, for example, between 0.1 cm and 1 cm. The number of bipolar electrodes in each electrode group 120 can be, for example, between 1 and 20, especially between 2 and 18, and can be, for example, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17.

[0111] It should be noted that the number of anodes in each electrode group 120 can be one or more, and the number of cathodes can also be one or more.

[0112] Bipolar electrodes are well known in the art (JP2004237165A, EP0065889A1, WO2012172118A1).

[0113] Preferably, at least one electrode group is non-separated.

[0114] In a specific embodiment (not shown in the figure), the electrolysis device 100 or system of the present invention may also include at least one switch or electrical control circuit, which is used to reverse the electrode polarity of at least one electrode group regularly (for example, pause for 5 minutes every 90 minutes), so that the current flows in one direction between the electrodes first and then reverses (bipolar operation). The purpose of reversing the electrode polarity is to remove or prevent the accumulation of deposits (such as calcium precipitation) on the electrode surface during operation. This operation can improve the operating performance of the electrodes and extend their service life. When reversing the polarity, it is best to set a 5-minute pause after the depolarization and repolarization of the electrodes, which helps to prevent short circuits between the electrodes of at least one electrode group 120. Short circuits may gradually damage the electrodes. The electrode polarity reversal and pause time can be controlled by a control unit 600, which will be described in detail below.

[0115] Preferably, the (at least one) electrode group 120 is configured or adapted to be inserted into the electrolysis reaction chamber 110 through an opening 114 on the inner wall of the electrolysis reaction chamber 110 in a detachable and sealed manner, so that during operation, the electrodes of the (at least one) electrode group 120 are at least partially immersed in the brine solution to be electrolyzed. The positioning and fixation of the electrode group 120 on the inner wall of the electrolysis reaction chamber 110 can be achieved by any means considered suitable by those skilled in the art, especially by inserting the (at least one) electrode group 120 through the inner wall by bayonet fitting or screwing. The diameter of the opening 114 on the inner wall 112 is about 90 mm, for example.

[0116] In a specific embodiment (not shown in the figures), the (at least one) electrode assembly 120 has a cylindrical or parallelepiped box structure and can be inserted into the electrolysis reaction chamber 110. The periphery of the electrode assembly is provided with a plurality of adapted openings or perforations. On the one hand, during operation, the (at least one) electrode assembly remains in contact with the aqueous solution to be electrolyzed. On the other hand, solid alkali metal chlorides (such as sodium chloride) cannot deposit inside the electrode assembly 120 and cause a short circuit in the electrolysis device 100.

[0117] As Figure 5 shown, in a specific embodiment, the electrolysis reaction chamber 110 is provided with a plurality of elongated hollow tubes 121. These hollow tubes extend along the horizontal axis and are respectively arranged inside the reaction chamber 110. Each hollow tube 121 serves as a support element for an electrode assembly 120. On the one hand, this facilitates the insertion of the electrode assembly 120 into the reaction chamber 110. On the other hand, it facilitates the removal of the electrode assembly 120 from the reaction chamber 110, for example, when electrode inspection and / or electrode replacement are required. In practical applications, each elongated hollow tube 121 is provided with perforations on its periphery. The function is to ensure that the electrodes of the (at least one) electrode assembly 120 inserted into the hollow tube 121 can contact the saline solution to be electrolyzed. Another function of such peripheral perforations is to prevent solid alkali metal chlorides (such as sodium chloride) from depositing between the electrodes of the (at least one) electrode assembly (120) and causing a short circuit in the electrolysis device. The elongated hollow tubes can be made of a material that is substantially the same as or similar to that of the reaction chamber 110. The diameter of its peripheral perforations can be 10 millimeters or less.

[0118] As Figure 6 shown, one end of the elongated hollow tube 121 is fixed to the inner wall 112 of the reaction chamber 100. It is provided with an external thread 119 for helically fixing an electrode assembly 120 with a self-reversing thread (not shown in the figures). Obviously, in addition to Figure 6 the fixing method or means shown, other fixing methods or means can also be used to ensure that the electrode assembly 120 is fixed to the elongated hollow tube 121 in a reversible and sealed manner.

[0119] Regarding the arrangement of the (at least one) electrode assembly 120 in the electrolysis reaction chamber 110, reference can be made to the patent application WO2012172118A1 under the applicant's name.

[0120] Generally, as Figure 2 , Figure 3 and Figures 8 to 12As shown, a cover plate 130 is provided above the electrolysis reaction chamber 110. The cover plate is configured or adapted to seal the upper opening 111 of the reaction chamber 110. The cover plate 130 is detachable, which on the one hand facilitates loading solid alkali metal chloride into the reaction chamber 110, and on the other hand provides a convenient passage to enter the interior of the reaction chamber 110 for evacuation and / or cleaning operations within the reaction chamber 110. The cover plate 130 is made of a material that is substantially the same as or similar to that of the reaction chamber 110, especially PVC, ABS or PC materials.

[0121] The cover plate 130 can be fixed to the reaction chamber by screws. As Figure 5 shown, external threads 113 are provided on the upper part of the reaction chamber 110 for fixing the cover plate 130 with self-reversing threads by screws (not shown in the figure). Obviously, in addition to Figure 5 the manner or method shown, other fixing means or methods can also be used to ensure the reversible closure of the reaction chamber 110. Examples of the above other means or methods include those commonly used in the opening and closing systems of pressure cookers.

[0122] In addition, the cover plate 130 can be equipped with a suitable sealing ring (not shown in the figure), such as an elastomeric sealing ring, to ensure or enhance the sealing between the reaction chamber 110 and the cover plate 130.

[0123] As Figures 2 to 5 and Figures 8 to 12 shown, the cover plate 130 is equipped with a conduit 200 (referred to as a communication conduit). This conduit is used to achieve fluid communication between the inside and outside of the electrolysis reaction chamber 110. The communication conduit 200 can be used to inject water into the electrolysis reaction chamber 110 to dissolve the solid alkali metal chloride stored in the reaction chamber (through the upper opening 111) to form an aqueous chloride ion solution to be electrolyzed. The communication conduit 200 can also be used to transfer hydrogen gas, at least part of hypochlorous acid, and chlorine gas (if necessary) generated by electrolysis in the reaction chamber 110 from the reaction chamber 110 to a dilution tank 300 dedicated to the preparation of disinfectant solution. The specific details will be further described below.

[0124] The communication conduit 200 can be made of a material that is substantially the same as or similar to that of the reaction chamber 110 or the cover plate 130, especially PVC, ABS or PC materials. Preferably, it is a cylindrical tube structure with a circular bottom. When in use, the lower end of the conduit passes through the cover hole 131 of the detachable cover plate 130 into the reaction chamber 110. The non-fixed upper end of the communication conduit 200 is used to connect to the dilution tank 300, and the specific connection method will be described in detail below.

[0125] The communication conduit 200 can be integrally formed with the cover plate 130 or fixedly installed on the cover plate 130 in a sealed manner, such as through a rubber sealing ring (not shown in the figure).

[0126] In a specific embodiment of the present invention (not shown in the figures), the electrolysis reaction chamber may also be provided with an outlet opening at its lower part for evacuation. This outlet opening can be closed by any suitable closing device, such as a plug, a cock or other tools.

[0127] Examples of electrolysis devices that can be used in conjunction with the system of the present invention have been described in detail in the patent application WO2012172118A1 under the applicant's name, or have been marketed under the trade name CHLOR'IN (https: / / www.chlor-in.com / concept-chlor-in-p3.php).

[0128] In the drawings, the conduit 200 is a straight or substantially straight vertical conduit, but an inclined conduit, or a vertical or inclined spiral conduit can also be used.

[0129] Dilution tank

[0130] The system according to the present invention further includes a dilution tank 300, which is used to dilute hypochlorous acid from at least one electrolysis device and water provided by a water source S to prepare a disinfectant solution.

[0131] The dilution tank 300 is located above at least one electrolysis device 100. As described above, the number of electrolysis devices can be 1, 2, 3 or more than 3. As Figure 2 、 Figure 3 and Figure 4 shown, the dilution tank 300 is located above 1, 2 and 3 electrolysis devices 100 respectively. The number of electrolysis devices 100 is selected according to the expected overall performance (for example, the production time of the hypochlorous acid disinfectant solution, the expected hypochlorous acid content in the disinfectant solution). In fact, the applicant has verified that in a dilution tank 300 filled with a given amount of water, the more the number of electrolysis devices, the more significant the effect that the disinfectant solution reaches the established hypochlorous acid concentration in a shorter time. This is highlighted in Example [Table 1], and proves the influence of the number of electrolysis devices 120 on the production time of the disinfectant solution according to the present invention.

[0132] The upper part of the dilution tank 300 according to the present invention is provided with a water inlet 302, and at least one bottom outlet (or opening) 303 (one bottom outlet for each electrolysis device) is provided at the bottom 305.

[0133] The water inlet 302 is dedicated to introducing water into the dilution tank 300. It is designed to be connected to a water source "S", such as a faucet, a municipal water supply pipe or other water supply devices.

[0134] In practical applications, the water injected into the dilution tank 300 can be municipal tap water, or natural spring water, distilled water, deionized water or filtered water can also be used.

[0135] In addition, in a specific embodiment (not shown in the figures), a water filter can also be installed between the water source "S" and the inlet 302 of the dilution tank 300 in the system of the present invention. The function of this water filter is to remove or at least reduce the organic compounds (or organic pollutants) that may be present in the water, which may interact with chlorine, especially with the electrolysis products of saturated sodium chloride water. This water filter can be any type of filter known to those skilled in the art, such as a granular filter (filter element, microfiltration membrane, sand filter); an activated carbon filter; an ultrafiltration membrane; a membrane contactor or a gas filtration membrane.

[0136] The bottom outlet 303 of the dilution tank 300 is configured or adapted to connect to the communication conduit 200 of the electrolysis device 100 to ensure fluid communication between the dilution tank 300 and the electrolysis reaction chamber 110 of the electrolysis device 100.

[0137] The bottom outlet 303 can be connected to the communication conduit 200 of the electrolysis device 100 through, for example, any suitable type of quick-sealing joint known to those skilled in the art (see, for example, US5580099A, US20190063652A1, EP0829671A2, US20180252347A1).

[0138] "The bottom outlet 303" refers to the bottom opening of the dilution tank 300, or a suitable bottom conduit inserted into the bottom opening of the dilution tank 300, and this bottom conduit can be permanently fixed or detachably installed on the dilution tank 300.

[0139] The dilution tank 300 can adopt various suitable forms (for example, a parallelepiped or a cylinder with an elliptical cross-section, or other forms) and sizes to best adapt to the expected application scenarios of the reaction chamber 110 and the system of the present invention. In actual applications, the dilution tank 300 adopts a parallelepiped structure with a square or rectangular cross-section. The capacity of the dilution tank 300 is 1 liter to 500 liters or more. Obviously, the dilution tank 300 of the present invention is not limited to the above forms or sizes.

[0140] In actual applications, the dilution tank 300 can be made of materials that are basically the same or similar to those of the reaction chamber 110, especially PVC, ABS or PC materials. Preferably, it can avoid environmental light irradiation, for example, by using an environmental light shading auxiliary device (not shown in the figures). This shading auxiliary device can adopt a box or cabinet structure, and its inner wall is made of opaque materials, such as but not limited to wood, opaque plastics (such as PVC, PEHD), frosted glass, metals (such as stainless steel).

[0141] In a specific embodiment of the present invention (not shown in the figures), the dilution tank 300 may also be provided with an outlet opening at its lower part for distributing the disinfectant solution or emptying the dilution tank 300. The outlet opening may be closed, for example, by a cock or connected to a storage tank suitable for receiving the disinfectant solution or a hose for distributing the disinfectant solution by means of a connecting device (e.g., a pipe).

[0142] In a specific embodiment of the present invention (not shown in the figures), the dilution tank 300 may further include a bubble-breaking device for breaking the chlorine gas bubbles that may be generated in the electrolysis reaction chamber 110 of at least one electrolysis device 100, thereby promoting the dissolution of chlorine gas in water; the bubble-breaking device is arranged at the bottom of the dilution tank 300 and is at least flush with the conduit 200 for realizing the fluid communication between the electrolysis reaction chamber and the dilution tank 300. The bubble-breaking device may be composed of at least one perforated plate, and the diameter of the perforation is sufficient to reduce the bubbles to a size that promotes the dissolution of chlorine gas in water. Preferably, the diameter of the perforation of the at least one plate is less than 5 mm, preferably less than 1 mm. More preferably, the bubble-breaking device is composed of multiple perforated plates. These plates are generally arranged in a stacked manner such that the perforations of two adjacent plates are staggered with each other.

[0143] In an alternative embodiment (not shown in the figures), the bubble-breaking device is composed of a stainless steel metal or plastic (e.g., PVC) filter screen, and the mesh size is less than 5 mm, preferably less than 1 mm.

[0144] Use of the system according to the present invention

[0145] The system according to the present invention can be installed in the manner described below, and this installation manner can be directly derived from the description combined with Figure 1 above, but the description of the installation or use manner of the system in this specification should not be understood as having a restrictive meaning.

[0146] Step 1: Starting from the electrolysis reaction chamber 110, which is already equipped with (at least) one electrode group 120 in practical applications. Load an alkali metal chloride (such as solid sodium chloride) into the electrolysis reaction chamber. It should be noted that the amount of the alkali metal chloride (such as sodium chloride) loaded in the electrolysis reaction chamber should be sufficient to prepare an aqueous solution containing a partially dissolved state of the alkali metal chloride (such as sodium chloride), such as a brine solution or a saturated aqueous solution of the alkali metal chloride. It should be noted that the solubility of sodium chloride in water at 0 °C is about 357 g / L. In a specific embodiment, about 25 kg of sodium chloride in granular form, about 15 g per granule, is loaded into an electrolysis reaction chamber with a volume of about 40 L. It should also be noted that the granular sodium chloride of about 15 g per granule is sold by K+S Minerals and Agriculture GmbH of Germany under the trade name Provided by PRO. In an alternative embodiment of this embodiment, potassium chloride or a mixture of sodium chloride and potassium chloride can be used to prepare the aqueous solution to be electrolyzed.

[0147] Step 2: Seal the electrolysis reaction chamber 110 using the detachable cover plate 130.

[0148] Step 3: Load an alkali metal chloride (such as sodium chloride) into the electrolysis reaction chamber 110, seal the reaction chamber with the cover plate 130, and then place the reaction chamber below the dilution tank 300. Combining with the above specific embodiment, for at least one electrolysis reaction chamber with a capacity of about 40 liters, a dilution tank with a capacity of 260 liters is selected.

[0149] Step 4: Connect the conduit 200 of the electrolysis device 100 to the corresponding bottom outlet 303 of the dilution tank 300. As described above, the connection operation can be completed using any suitable type of quick-sealing device known to those skilled in the art. At this time, the dilution tank 300 and the electrolysis reaction chamber 110 of the electrolysis device 100 are in a fluid communication state.

[0150] Step 5: Connect the dilution tank 300 to the water source S via the appropriate water filter (if applicable) described above.

[0151] Step 6: Fill the dilution tank 300 and the electrolysis reaction chamber 110 with water. Among them, the electrolysis reaction chamber is filled with water through the bottom outlet 303 of the dilution tank 300 and the conduit 200 of the electrolysis reaction chamber 110 connected to the bottom outlet 303. It should be noted here that the advantage of using a solid alkali metal chloride (such as sodium chloride) is that when the electrolysis reaction chamber 110 is filled with water, the alkali metal chloride salt will always remain at the bottom of the reaction chamber.

[0152] Step 7: Wait for a sufficient time for at least part of the alkali metal chloride (such as sodium chloride) to dissolve in water to form chloride ions. In practical applications, this waiting time is about 5 minutes to 1 hour.

[0153] Step 8: After the entire system is assembled, use the energy source 101 to power at least one electrolysis device to start electrolysis.

[0154] In practical applications, the supply current of the electrodes of at least one electrode group 120 (or the electrodes of at least one electrolysis device 100) is direct current. As an alternative embodiment, the electrolysis described in the present invention can be carried out using pulsed current.

[0155] The electrolysis occurring in the electrolysis reaction chamber 110 is usually carried out in the range of about pH 6 to 8, and the working voltage is between 1 volt and 15 volts, preferably between 2 volts and 10 volts.

[0156] The current density range of the direct current (and / or pulsed current) used is from 0.1 A / dm² to 10 A / dm², or above 10 A / dm². Preferably, electrolysis is carried out using a direct current (and / or pulsed current) within the range of 0.1 A / dm² to 5 A / dm².

[0157] After sufficient electrolysis time to obtain a hypochlorous acid disinfectant solution reaching the expected free chlorine content, electrolysis can be terminated (this will be described in detail below).

[0158] During electrolysis, at least part of the chloride ions contained in the aqueous solution in the electrolysis reaction chamber are oxidized at at least one anode of the electrolysis device, thereby generating chlorine gas (Cl 2(g) ) according to the reaction formula 4 mentioned above. The chlorine gas generated immediately reacts with the water in the aqueous solution, thereby generating hypochlorous acid (HClO (aq) ) and hydrochloric acid (HCl (aq) ) according to the reversible reaction formula 2 mentioned above. While the oxidation reaction of chloride ions occurs, a water reduction reaction occurs at at least one cathode of the electrolysis device, generating hydrogen gas (H 2(g) ) and hydroxide ions (OH - ) according to the reaction formula 5 mentioned above. Therefore, generally speaking, an aqueous solution of an alkali metal chloride (such as sodium chloride) undergoes an electrolysis reaction within the pH range of 6 to 8 (the pH value of municipal tap water), thereby generating chlorine-containing products (chlorine gas, hypochlorous acid, and / or hypochlorite ions) and hydrogen gas in the electrolysis reaction chamber 110. However, the electrolysis reaction chamber is in fluid communication with the water-filled dilution tank 300.

[0159] The hydrogen gas and possibly part of the chlorine gas generated in the electrolysis reaction chamber 110 are successively discharged into the atmosphere via the conduit 220 of the reaction chamber, the bottom outlet 303 of the dilution tank 300, and the water-filled dilution tank 300.

[0160] On the other hand, the water in the dilution tank 300 and the aqueous solution in the electrolysis reaction chamber 110 together form a dynamic equilibrium system, which can automatically homogenize the concentrations of the chemical substances contained (including water, hypochlorous acid, and / or hypochlorite ions, chloride ions). This "irreversible" migration phenomenon of chemical substances helps to homogenize the system components, and this phenomenon corresponds to the so-called "diffusion" effect in physical chemistry.

[0161] Therefore, in this case, hypochlorous acid and / or hypochlorite ions and chloride ions tend to move (or migrate) from the aqueous solution in the electrolysis reaction chamber 110 to the dilution tank 300; while water moves (or migrates) in the opposite direction, that is, from the dilution tank 300 to the electrolysis reaction chamber 110.

[0162] It should be clearly pointed out that in the case of no agitation acceleration, this phenomenon occurs slowly in principle.

[0163] However, despite this highly unfavorable inherent perception, the inventors have still discovered an innovative value: by arranging the dilution tank 300 above the electrolysis reaction chamber 110 and achieving fluid communication between the two, and utilizing the migration of hydrogen gas bubbles and possibly chlorine gas bubbles generated in the aqueous solution within the electrolysis reaction chamber 110, highly efficient disinfectant solutions with a free chlorine (hypochlorous acid and / or hypochlorite ions) content that can reach or even exceed 1000 ppm can be prepared within an industrially acceptable time, such as less than 12 hours. In fact, this bubble migration generates minute vortices, thereby promoting the migration or diffusion of at least some hypochlorous acid molecules and / or hypochlorite ions (or chlorine-containing products) from a high-concentration medium (the aqueous solution in the electrolysis reaction chamber 110) to a low-concentration medium (the water in the dilution tank 300).

[0164] In addition, the electrolysis reaction can also be adjusted to promote the generation of gas (especially hydrogen) bubbles, thereby causing these bubbles to generate turbulence and forcing at least some hypochlorous acid to migrate from the electrolysis reaction chamber 110 to the dilution tank 301. In this regard, the authors of the present invention have confirmed that by increasing the number of electrodes in each electrode group 120 and / or the number of electrodes in each electrode device, the generation of the above-mentioned bubbles can be promoted, and the production time of hypochlorous acid disinfectant solutions with a predetermined or expected free chlorine content can be shortened.

[0165] Furthermore, the authors of the present invention have also unexpectedly discovered that the disinfectant solution prepared by the system of the present invention may contain alkali metal chlorides (such as sodium chloride), but its content is very low, less than 1 ppm, which is very advantageous for the disinfectant solution preparation method or system.

[0166] Here, the concept of "sufficient electrolysis time" mentioned above is further elaborated. In fact, the present invention supports users of the hypochlorous acid disinfectant solution preparation system to independently select the free chlorine content that best meets the requirements of their disinfection scenario, such as scenarios for air disinfection, hard or soft surface disinfection, medical device disinfection, skin disinfection, skin wound disinfection, plant disinfection (e.g., salad, fruits, vegetables, grapevines, plants), animal breeding site disinfection, etc.

[0167] In order to obtain a disinfectant solution with a predetermined free chlorine content that meets the expected usage scenario, users can also monitor the free chlorine content in the water in the dilution tank 300 during the production process. In addition, when the free chlorine content reaches the expected value, users can interrupt the electrolysis process of one or more electrolysis devices.

[0168] "Free chlorine" refers to hypochlorous acid (HClO) and hypochlorite ions (ClO - ).

[0169] The user can sample the disinfectant solution prepared in the dilution tank 300 and analyze the sample to determine its free chlorine content, so as to monitor the dynamic changes in the production process of hypochlorous acid disinfectant solution. The sample collection and analysis can be operated in an intermittent or continuous manner, and preferably in a continuous manner.

[0170] The intermittent determination of the free chlorine content in the disinfectant solution can be carried out by traditional analysis methods known to those skilled in the art: colorimetric titration, acid-base titration, amperometric titration, spectrophotometric analysis (see, for example, WO2013121294A1), and oxidation-reduction potential determination (ORP).

[0171] Preferably, as Figures 8 to 12 shown, the system of the present invention further includes a measuring device 400, and this measuring device includes:

[0172] - A sensor 411, which is used to measure the free chlorine content in the disinfectant solution prepared in the dilution tank 300,

[0173] - A display 412, which is used to display the free chlorine content measured by the sensor 411.

[0174] The free chlorine content threshold corresponds to a selected maximum value, and the free chlorine content of the disinfectant solution prepared in the dilution tank 300 shall not exceed this maximum value. This threshold is set by the user, for example, ≥5 ppm. This threshold is usually set to be selected from the range of 5 ppm to 3000 ppm, especially the range of 10 ppm to 1500 ppm. It should be particularly noted that the system of the present invention can be adjusted as needed. For example, in order to prepare a concentrated hypochlorous acid disinfectant solution, its free chlorine content can be controlled within the precise range of ≥3000 ppm to ≤10000 ppm.

[0175] The measuring device 400 and its sensor 411 and display 412 can adopt existing commercially available models. As Figure 8 shown, this device can be connected to the measuring interface below the current liquid level of the disinfectant solution in the dilution tank, or in actual application, as Figures 9 to 12 shown, this device can be installed on the recirculation loop 450.

[0176] The measuring device 400 uses its sensor 411 to continuously measure the free chlorine content of the disinfectant solution in the dilution tank, so as to track the production situation of the disinfectant solution in real time. Continuously display the free chlorine content measured by the sensor 411, so that the user can monitor the production situation of the hypochlorous acid disinfectant solution in real time, and when the user believes that the free chlorine content of the disinfectant solution is sufficient to meet the intended use, decide to interrupt the electrolysis process at any time.

[0177] In order to automatically monitor the production of the disinfectant solution, the system of the present invention may further include a control unit, as Figures 9 to 12as shown by 600 therein. The control unit 600 is operably connected to the measuring device 400 and is configured to perform the following operations: compare the free chlorine content measured by the sensor 411 with a free chlorine content threshold value, and interrupt electrolysis when the free chlorine content measured by the sensor 411 is equal to or higher than the free chlorine content threshold value.

[0178] The free chlorine content threshold value corresponds to a selected maximum value, and the free chlorine content of the disinfectant solution prepared in the dilution tank 300 shall not exceed this maximum value. The free chlorine content threshold value (or maximum value) can be selected within the range of free chlorine content ≥ 5 ppm, especially in the range of 5 ppm to 3000 ppm, such as in the range of 10 ppm to 1500 ppm.

[0179] In addition, the pH value of the disinfectant solution prepared in the dilution tank 300 is generally greater than 3 and less than 8, especially between 4 and 7.5. Preferably, this pH value is maintained or adjusted between 5 and 7, more preferably between about 5.1 and about 6.9, especially about 6.5.

[0180] It should be noted that the disinfectant solution prepared by the system of the present invention is applicable to various scenarios (for example, air disinfection, disinfection of animal and plant or human surfaces, disinfection of medical equipment, etc.), and can achieve the best effect when its pH value is within the range of 5.1 to 6.9, especially about 6.5.

[0181] In addition, preferably, the system of the present invention further includes a pH probe 413 for measuring or determining the pH value of the disinfectant solution in the dilution tank 300. This pH probe can adopt existing commercially available models. The probe is connected to a measurement interface below the liquid level of the disinfectant solution in the dilution tank 300 (as Figure 8 shown), or in actual applications, the probe is placed on the recirculation loop 450 (as Figures 9 to 12 shown). As an alternative implementation not shown in the figure, the pH probe can be immersed in the dilution tank 300 for measurement (for example, using the split probe digital pH meter model 2201LM of MOINEAU Instruments, France).

[0182] In actual applications, the pH probe 413 is integrated into the measuring device 400, and the measuring device includes a sensor 411. In addition, the measuring device 400 can also be configured to simultaneously display the pH value measured by the pH probe 413 and the free chlorine content value measured by the sensor 411 through a display 412.

[0183] The system of the present invention can also include a pH adjustment device (not shown in the figure), which can receive the signal sent from the pH probe 413 through the network and can be adapted to inject a pH regulator into the dilution tank in response to the signal sent from the pH probe 413.

[0184] "pH regulator" refers to any acidic or alkaline aqueous solution that does not change the physicochemical properties of hypochlorous acid. Preferably, the pH regulator is in the form of an aqueous solution containing an acid, and more preferably is selected from inorganic acids (such as boric acid, hydrochloric acid, phosphoric acid, and sulfuric acid) and / or organic acids (such as acetic acid, citric acid, ascorbic acid, and propionic acid).

[0185] Generally, the pH adjustment device further includes a metering pump that can inject a certain dose of pH regulator into the disinfectant solution.

[0186] The pH adjustment device (with the metering pump connected to the pH regulator storage tank) can adopt existing commercially available models. The metering pump can be connected to the dilution tank 300 (this embodiment is not shown in the figure) or arranged at any position in the recirculation loop, such as Figures 9 to 12 the loop 450 shown.

[0187] In practical applications, the pH probe 413 can continuously or periodically (for example, once every 10 minutes) measure the pH value of the disinfectant solution in the dilution tank. If the pH value measured by the probe 413 is higher or lower than the expected value (usually set within the range of 5 to 7, preferably about 5.1 to 6.9, especially about 6.5), the metering pump of the pH adjustment device will inject a certain dose of pH regulator to correspondingly lower or raise the pH value of the disinfectant solution until it reaches the expected value.

[0188] The pH adjustment device is usually arranged near the pH probe 413. As described above, this probe can be integrated into the measuring device 400.

[0189] The measurement and adjustment of the pH value of the disinfectant solution and the measurement of the free chlorine content can be automated through the control unit 600 described above.

[0190] In practical applications, as Figures 10 to 12 shown, the water inlet 302 of the dilution tank 300 is connected to the water source S via the water supply loop 420, and this loop is sequentially provided with valves (preferably solenoid valves 440 or 441) and a pump 430 along the direction of the dilution tank 300.

[0191] In order to ensure the homogeneous distribution of the disinfectant solution in the dilution tank 300 and measure parameters such as the pH value and free chlorine content of the disinfectant solution, the system described in the present invention may further include an external recirculation loop, such as Figure 10 shown in 450.

[0192] This external recirculation loop 450 can be composed of a sampling pipeline (such as Figures 10 to 11It is composed of a sampling pipeline 410 (shown as 410 in the figure) and a partial water supply circuit 420. The sampling pipeline 410 is used for sampling at least part of the disinfectant solution. One side of it is connected to the sampling outlet 307 on the dilution tank 300, and the other side is connected to a tap (shown as 421 in the figure) between the solenoid valve 440 and the pump 430 on the water supply circuit 420. This is intended to make at least part (or a small part) of the disinfectant solution in the circulation circuit 450 flow from the sampling outlet 307 to the water inlet 302 of the dilution tank 300 in a cycle.

[0193] In a possible implementation, as Figure 11 shown, the two-way solenoid valve 440 is replaced by a three-way solenoid valve 441. Among them, the first passage 441a is connected to the water source S, the second passage 441b is connected to the water inlet of the pump 430, and the third passage 441c is connected to the sampling pipeline 410. This third passage 441c replaces the tap 421 used in the previous implementation. When the first passage 441a of the solenoid valve 441 is closed and the second and third passages 441b and 441c are opened, it helps to form a recirculation circuit 450', which is equivalent to the aforementioned recirculation circuit 450.

[0194] In practical applications, as Figures 10 to 12 shown, the sampling outlet 307 is provided on the lower tank wall or bottom of the dilution tank 300, and the water inlet 302 is provided on the upper part of the dilution tank 300. Of course, this layout can be configured reversely, that is, the sampling outlet 307 is provided on the upper part of the dilution tank 300, and the water inlet 302 is provided on the lower part of the dilution tank.

[0195] As described above, a measurement sensor or probe (for measuring the pH value and free chlorine content) and a disinfectant solution pH value adjustment device can be provided at the recirculation circuit 450 or 450'. This enables the user to obtain various parameter information of the disinfectant solution in real time, so as to optimally monitor the production of the disinfectant solution and ensure that the expected concentration is achieved.

[0196] Preferably, a control unit 600 is used to control the solenoid valve 440 or 441 and the pump 430.

[0197] More preferably, the dilution tank 300 is equipped with a disinfectant solution liquid level detector, so as to optimize the operation of the recirculation circuit 450 or 450' and the system described in the present invention.

[0198] In a specific implementation, as Figures 10 to 11 shown, the dilution tank 300 is provided with three liquid level detectors, namely a low liquid level detector N1, a high liquid level detector N2, and a middle liquid level detector N3. The middle liquid level detector is located between the low liquid level detector N1 and the high liquid level detector N2.

[0199] In another implementation, as Figure 12As shown, the dilution tank 300 is provided with a tubular gauge 310, which is located on the outer wall (or one of the tank walls) of the dilution tank 300 and is arranged perpendicular and parallel to the dilution tank. As Figure 12 shown, the lower end 311 of the tubular gauge 310 forms a fluid communication with the lower opening 306 of the dilution tank 300, and the upper end 312 forms a fluid communication with the upper opening 308 of the dilution tank. In addition, a low liquid level detector N1' is provided at the opening 306 (or the lower end 311) of the dilution tank 300, a high liquid level detector N2' is provided at the opening 308 (or the upper end 312) of the dilution tank 300, and a medium liquid level detector N3' is provided between the low liquid level detector N1' and the high liquid level detector N2'.

[0200] Each liquid level detector N1, N2 and N3 (or N1', N2' and N3') is connected to the control unit 600, and the control unit can be configured to perform a number of control operations, such as:

[0201] - In response to a signal sent by the low liquid level detector N1 (or N1'), inject water into the dilution tank 300;

[0202] - In response to a signal sent by the high liquid level detector N2 (or N2'), interrupt the water injection into the dilution tank 300, and then introduce the disinfectant solution into the circulation loop 450 (or 450');

[0203] - In response to a signal sent by the medium liquid level detector N3 (or N3'), start the measuring device 400 to measure the free chlorine content in the dilution tank 300.

[0204] In practical applications, when injecting water into the dilution tank 300, if the low liquid level detector N1 (or N1') detects that the water level or the disinfectant solution level in the dilution tank 300 is equal to or lower than the lowest preset level, a low liquid level signal will be sent to the control unit 600. The control unit will control the solenoid valve 440 (or 441) to open the water supply circuit 420, so as to supply water to the dilution tank 300. If the solenoid valve 441 is used, the control unit 600 will control the solenoid valve to open the passages 441a and 441b, and at the same time close the passage 441c.

[0205] For the situation of interrupting water injection and circulating the disinfectant solution in the circulation loop, when the high liquid level detector N2 (or N2') detects that the water level or the disinfectant solution level in the dilution tank is equal to or higher than the highest preset level, a high liquid level signal will be sent to the control unit 600. The control unit will control the solenoid valve 440 to be completely closed (or the solenoid valve 441 closes its passage 441a and opens its passages 441b and 441c), and at the same time control the pump 430 to start sucking the part of the disinfectant solution that overflows outside the dilution tank 300, so that this part of the disinfectant solution can flow from the recirculation loop 450 (or 450') to the water inlet 302 of the dilution tank 300.

[0206] The system according to the present invention can be equipped with a forced operation and an automatic operation mechanism.

[0207] Reference Figures 10 to 12 , the control unit 600 may include a user interface 601, which includes a plurality of buttons for performing a plurality of operations, such as: selecting a forced operation or an automatic operation mechanism, adjusting thresholds such as pH and free chlorine content, and managing the production of disinfectant solution (using one or more electrolysis devices and / or electrode groups). The user interface 601 can also be used to control each element of the system according to the present invention through the control unit 600, such as:

[0208] - the energy source 101 that supplies power to one or more electrode groups 120 of at least one electrolysis device 100 is started or stopped, and / or

[0209] - at least one electrolysis device 100 is started or stopped, and / or

[0210] - the measuring device 400 is started or stopped, and / or

[0211] - the solenoid valve 440 is opened or closed, and / or

[0212] - the pump 430 is started or stopped, and / or

[0213] - the pH adjustment device is started or stopped, and / or

[0214] - the electrode polarity of one or more electrode groups 120 is reversed, and the pause time between each polarity reversal is controlled if necessary.

[0215] The user interface 601 also enables the user to sequentially query the following information: the system operation status, the production status of hypochlorous acid disinfectant solution, the pH value measured by the pH probe 413, the free chlorine content value measured by the sensor 411, or the operation duration of one or more electrolysis devices 100 recorded by the control unit 600 over time.

[0216] During the execution of the forced operation, the control unit 600 will only interrupt the power supply to one or more electrolysis devices 100 when the expected free chlorine content of the disinfectant solution is reached or exceeded.

[0217] During the execution of the automatic operation, the control unit 600 manages the production operation of the hypochlorous acid disinfectant solution. For example, when there are multiple electrolysis devices, it allows or prohibits the power supply to one or more electrolysis devices 100, and / or when each electrolysis device 100 has multiple electrode groups, it allows or prohibits the power supply to one or more electrode groups 120.

[0218] The control unit 600 can continuously monitor the production of the disinfectant solution in the dilution tank. When the free chlorine content measured by the sensor 411 exceeds the preset threshold and it is necessary to interrupt the power supply to one or more electrode groups of multiple electrolysis devices, it controls to stop one or more electrolysis devices 100.

[0219] The control unit 600 can continuously monitor the production of the disinfectant solution in the dilution tank. When the pH value measured by the pH probe exceeds the preset threshold range and the control unit 600 detects an abnormal operation of the pH adjustment device (for example, the device can no longer adjust the pH value back to the expected level by injecting the pH regulator) and it is necessary to cut off the power supply to one or more electrode groups of multiple electrolysis devices, it controls to stop one or more electrolysis devices 100.

[0220] In a specific embodiment not shown in the figure, the system of the present invention further includes a remote information transmission system 603 and / or a storage system for various information of the system of the present invention. These information include:

[0221] - Production percentage,

[0222] - Measured pH value of the disinfectant solution,

[0223] - Measured free chlorine content value of the disinfectant solution,

[0224] - Set thresholds, especially pH threshold and free chlorine content threshold,

[0225] - Operating time of the system of the present invention, so as to determine the replacement time of at least one electrode group 120,

[0226] - Polarity inversion period of at least one electrode group 120,

[0227] - Each power failure event,

[0228] - Automatic operation or forced operation,

[0229] - Diagnostic trigger.

[0230] The above information is recorded at least three times a day, with a 30-day cycle. Preferably, the information related to the diagnosis of the system of the present invention and power failure events is retained.

[0231] Preferably, the control unit 600 is provided with a type 82 liquid crystal display screen 602 (Liquid Crystal Display, LCD) for communicating information related to the operation of the system of the present invention to the user.

[0232] For more information about the control unit 600 (its characteristics and uses), useful information can be referred to the patent application WO2012172118A1 under the applicant's name.

[0233] Generally speaking, the system described in the present invention can operate in manual and / or semi-automatic and / or fully automatic modes, and is used to monitor the production of hypochlorous acid disinfectant solution with a free chlorine content meeting the user's expectations.

[0234] The present invention also provides a method for preparing a disinfectant solution. The method described in the present invention includes the following steps:

[0235] -a) Provide the system described in the present invention;

[0236] -b) Inject water into the dilution tank 300 and the electrolysis reaction chamber 110 described in the present invention;

[0237] -c) Apply an electric current to the electrodes of at least one electrode group 120 of at least one electrolysis device 100 to electrolyze an aqueous solution containing chloride ions in the electrolysis reaction chamber 110, thereby generating hypochlorous acid. Among them, at least part of the hypochlorous acid migrates from the electrolysis reaction chamber 110 to the dilution tank 300 through the conduit 200 and is mixed and diluted with the water in the dilution tank 300 to form a disinfectant solution;

[0238] -d) Measure the free chlorine content of the disinfectant solution prepared in the dilution tank 300;

[0239] -e) When the free chlorine content measured in step d) reaches the expected free chlorine content value of the disinfectant solution, interrupt the electrolysis.

[0240] The expected free chlorine content value refers to the free chlorine content value that the user hopes to reach or selects, and this content value can meet the user's concentration expectation for the hypochlorous acid disinfectant solution.

[0241] The method described in the present invention may also include step f): Measure the free chlorine content of the disinfectant solution prepared in the dilution tank through the adaptation sensor 411.

[0242] The method described in the present invention may also include step g): Execute the electrolysis interruption operation in step e) through the control unit 600. This control unit is used to compare the free chlorine content measured by the sensor 411 in step f) with the free chlorine content threshold, and interrupt the electrolysis when the free chlorine content measured by the sensor 411 is equal to or higher than the free chlorine content threshold. Preferably, the free chlorine content threshold is set to the maximum value selected from the range of 5 ppm to 3000 ppm, especially the range of 10 ppm to 1500 ppm.

[0243] The method described in the present invention may also include step h): Measure at least one inherent parameter of the disinfectant solution prepared in the dilution tank 300, and this inherent parameter can be selected from the list of pH value, temperature, conductivity, and hardness parameters.

[0244] The method described in the present invention may also include step g): Adjust the pH value of the disinfectant solution prepared in the dilution tank 300.

[0245] Preferably, the voltage applied to the electrode in step c) is between 1 volt and 15 volts, preferably between 2 volts and 10 volts.

[0246] Preferably, the pH value range of the hypochlorous acid disinfectant solution is about 5.1 to 6.9, preferably 6.5. The above pH value range is the optimal range for the intended use scenarios of the disinfectant solution prepared according to the present invention.

[0247] Each element of the system of the present invention (dilution tank, electrolysis device, connecting conduit, pipeline, cable, pH and free chlorine content measuring and regulating device, control unit, etc.) can be arranged as a set of compact components, which are small in volume, convenient for transportation and installation, and suitable for the production of hypochlorous acid disinfectant solution.

[0248] In practical applications, the complete set of systems of the present invention is supported by a vertical support structure, which can be used to support at least the dilution tank 300 and at least one electrolysis device 100 (and its electrolysis reaction chamber 110), thereby ensuring the overall assembly stability. The vertical support structure can adopt, for example, a frame structure, which defines a space dedicated to the production of the disinfectant solution of the present invention, and its configuration includes:

[0249] - A first compartment, which is installed on the frame and in which at least one electrolysis device 100 and a circulation pump 430 (if necessary) can be arranged;

[0250] - A second compartment, which is arranged above the first compartment and in which the dilution tank 300 can be arranged. At least one lower opening is provided in the lower part of the second compartment for the connecting conduit 200 of at least one electrolysis device to pass through;

[0251] - The outer walls of the first compartment PC1 and / or the second compartment PC2, which are used to support other elements of the system of the present invention, such as a power supply 101, a water supply circuit, a cable, a control unit 600 (if necessary), a solenoid valve 440 (or 441), and other components / elements considered to be within the scope of the present invention.

[0252] Obviously, the system of the present invention is not limited to the above assembly form. In particular, a frame structure can be considered, which includes two opposite parallel side walls (or two pairs of opposite side columns), an upper horizontal platform for supporting the dilution tank 300, and a lower horizontal platform (or base or pedestal) for supporting at least one electrolysis device 100 and a pump 430 (if necessary). The upper and lower platforms are fixedly connected to the opposite side walls (or pairs of opposite side columns), and at least one lower opening is provided in the upper platform for installing the corresponding connecting conduit 200 of at least one electrolysis device.

[0253] An example of the compact assembly of the system of the present invention is as followsFigure 4 as shown

[0254] In addition, one or more features described in only one embodiment may be combined with one or more other features described in only another embodiment. Similarly, one or more features described in only one embodiment may be extended to other embodiments, even if the one or more features are only described in combination with other features:

[0255] - The electrolysis reaction chamber 110 or its cover plate 130 may be equipped with a pressure gauge for monitoring the pressure of the electrolysis reaction chamber 110;

[0256] - The dilution tank 300 may be equipped with a cover plate or a perforated top plate for discharging gases (hydrogen, and chlorine when applicable);

[0257] - The electrodes of at least one electrode group 120 may be solid or perforated;

[0258] - One or more electrolysis devices 100 may be assembled on a base or pedestal;

[0259] - The support structure for supporting the system described in the present invention may be equipped with rolling devices, such as casters, to facilitate the movement of the entire system.

[0260] Examples

[0261] Hypochlorous acid disinfectant with a free chlorine content of 250 ppm was subjected to production tests under the following operating conditions:

[0262] - Dilution tank 300 = 260 liters,

[0263] - Electrolysis reaction chamber = 40 liters,

[0264] - Electrode group = Each electrode group includes 7 flat electrodes arranged in parallel with alternating polarities. The flat electrode is 210 mm long and 55 mm wide and is made of a titanium plate coated with titanium oxide, ruthenium oxide, and iridium oxide coatings,

[0265] - Ambient temperature (about 25 °C),

[0266] - The pH value of the disinfectant was maintained at 6.5,

[0267] - Applied voltage = between 4 volts and 6 volts,

[0268] - Current intensity = between 15 amperes and 30 amperes.

[0269] [Table 1]

[0270]

[0271] As can be seen from the above table, when preparing hypochlorous acid disinfectant with a predetermined free chlorine content, the more the number of electrolysis devices and / or electrode groups, the shorter the production time of the disinfectant.

[0272] The present invention is not limited to the described embodiments. Further, in the claims, any reference signs in parentheses shall not be construed as limiting the claims. Additionally, when using "comprising", "including" or "containing" and their conjugate verbs, the presence of other elements or steps not stated in the claims is not excluded. Obviously, one or more features described in only one embodiment can be combined with one or more other features described in only another embodiment. Similarly, one or more features described in only one embodiment can be extended to other embodiments.

Claims

1. A system for preparing hypochlorous acid disinfectant solution, characterized in that, Comprising: - A dilution tank (300) dedicated to preparing the disinfectant solution, the dilution tank (300) being provided with a water inlet (302) for injecting water therein; - At least one electrolysis device (100), which is arranged below the dilution tank (300) and comprises: -- An electrolysis reaction chamber (110) for storing solid alkali metal chloride; -- At least one electrode group (120), which includes at least one anode and at least one cathode and is arranged in the electrolysis reaction chamber (110); -- A conduit (200) for achieving fluid communication between the electrolysis reaction chamber (110) and the dilution tank (300), wherein the conduit (200) is arranged such that when water is injected into the dilution tank (300), water is synchronously injected into the electrolysis reaction chamber (110) to dissolve a part of the solid alkali metal chloride stored in the electrolysis reaction chamber (110), thereby forming an aqueous solution containing chloride ions; and such that when the aqueous solution in the electrolysis reaction chamber (110) is electrolyzed by the electrode group (120) to generate hypochlorous acid, at least part of the hypochlorous acid can migrate from the electrolysis reaction chamber (110) to the dilution tank (300) and be mixed and diluted with the water therein to form the disinfectant solution.

2. The system according to claim 1, characterized in that, By adjusting the electrolysis of the aqueous solution in the electrolysis reaction chamber (110) of the at least one electrolysis device, bubbles are generated, and the bubbles generate turbulence, and the turbulence can force at least part of the hypochlorous acid to migrate from the electrolysis reaction chamber (110) to the dilution tank (301) through the conduit (200).

3. The system for preparing disinfectant solution according to claim 1 or 2, characterized in that, The at least one electrolysis device (100) can be one, two, three or more than three electrolysis devices (100).

4. The system for preparing disinfectant solution according to any one of claims 1 to 3, characterized in that, The at least one electrode group (120) can be one, two or more than two electrode groups (120).

5. The system for preparing disinfectant solution according to any one of claims 1 to 4, characterized in that, The at least one electrode group (120) further includes a plurality of bipolar electrodes, and the plurality of bipolar electrodes are interspersed between the anode and the cathode of the at least one electrode group (120).

6. The system for preparing disinfectant solution according to claim 5, characterized in that, The at least one anode, the at least one cathode and the plurality of bipolar electrodes of the at least one electrode group (120) are all in the shape of flat plates arranged parallel to each other and at equal intervals.

7. The system for preparing disinfectant solution according to any one of claims 1 to 4, characterized in that, The at least one electrode group (120) includes a plurality of anodes and a plurality of cathodes, and the plurality of anodes and the plurality of cathodes are in the shape of flat plates arranged in parallel with alternating polarities.

8. The system for preparing disinfectant solution according to any one of claims 1 to 7, characterized in that, The electrolysis reaction chamber (110) of the at least one electrolysis device (100) has a capacity of at least 10 liters.

9. The system for preparing disinfectant solution according to any one of claims 1 to 8, characterized in that, The dilution tank (300) includes a bubble breaking device for breaking the chlorine bubbles that may be generated in the electrolysis reaction chamber (110) of the at least one electrolysis device (100), thereby promoting the dissolution of chlorine in water; the bubble breaking device is arranged at the bottom of the dilution tank (300) and is at least flush with the conduit (200) for achieving fluid communication between the electrolysis reaction chamber (110) and the dilution tank (300).

10. The system for preparing disinfectant solution according to claim 9, characterized in that, The bubble-breaking device consists of at least one perforated plate, and the diameter of the perforations is sufficient to reduce the bubbles to a size that promotes the dissolution of chlorine gas in water.

11. The system for preparing disinfectant solution according to claim 10, characterized in that, The diameter of the perforations in the at least one plate is less than 5 mm, preferably less than 1 mm.

12. The system for preparing disinfectant solution according to claim 11 or 12, characterized in that, The bubble-breaking device consists of multiple perforated plates, and the multiple plates are arranged in a stacked manner such that the perforations of two adjacent plates are staggered with each other.

13. The system for preparing disinfectant solution according to any one of claims 1 to 12, characterized in that, It further includes a measuring device (400), and the measuring device includes: - A sensor (411) for measuring the free chlorine content in the disinfectant solution prepared in the dilution tank (300); - A display (412) for displaying the free chlorine content measured by the sensor (411).

14. The system for preparing disinfectant solution according to any one of claims 1 to 13, characterized in that,It further includes an adjusting device for adjusting the pH value of the disinfectant solution prepared in the dilution tank (300).

15. The system for preparing a disinfectant solution according to any one of claims 1 to 14, characterized in that, It further includes a control unit (600), the control unit is operably connected to the measuring device (400) for measuring the free chlorine content, and the control unit (600) is configured to perform the following operations: compare the free chlorine content measured by the sensor (411) with a free chlorine content threshold, and interrupt the electrolysis when the free chlorine content measured by the sensor (411) is equal to or higher than the free chlorine content threshold.

16. The system according to claim 15, characterized in that, The free chlorine content threshold is set to the maximum value selected from the range of 5 ppm to 3000 ppm, especially the range of 10 ppm to 1500 ppm.

17. The system for preparing a disinfectant solution according to any one of claims 1 to 16, characterized in that, The water inlet (302) of the dilution tank (300) is connected to a water source (S) via a water supply circuit (420), and a solenoid valve (440, 441) and a circulation pump (430) are sequentially provided along the direction of the dilution tank (300) in the water supply circuit.

18. The system for preparing a disinfectant solution according to claim 17, characterized in that, The dilution tank (300) is provided with a sampling outlet (307) for sampling the disinfectant solution. The sampling outlet (307) is connected to a tap (421, 441c), and the tap is located between the solenoid valve (440) and the circulation pump (430) in the water supply circuit (420), such that a sampling pipeline (410) and the circulation pump (430) and a part of the water supply circuit (420) behind the circulation pump (430) form a recirculation circuit (450, 450'), and the recirculation circuit is used to circulate the disinfectant solution from the sampling outlet (307) back to the water inlet (302).

19. The system for preparing a disinfectant solution according to claim 18 in combination with claim 13, characterized in that, The measuring device (400) for measuring the free chlorine content is located on the recirculation circuit (450, 450'), specifically on the sampling pipeline (410), to ensure continuous measurement of the disinfectant solution.

20. A method for preparing a hypochlorous acid disinfectant solution, characterized in that, It includes the following steps: a) Provide a system according to any one of the preceding claims; b) Fill water into the dilution tank (300) of the system. When filling water into the dilution tank (300), water is simultaneously filled into the electrolysis reaction chamber (110) of at least one electrolysis device (100) of the system through the conduit (200) for realizing fluid communication between the electrolysis reaction chamber (110) and the dilution tank (300) to dissolve a part of the alkali metal chloride stored in the electrolysis reaction chamber (110), thereby forming an aqueous solution containing chloride ions; c) Apply current to the electrodes of at least one electrode group (120) of at least one electrolysis device (100) to electrolyze the aqueous solution containing chloride ions in the electrolysis reaction chamber (110), thereby generating hypochlorous acid. At least part of the hypochlorous acid migrates from the electrolysis reaction chamber (110) to the dilution tank (300) through the conduit (200) and is mixed and diluted with the water in the dilution tank (300) to form the disinfectant solution; d) Measure the free chlorine content of the disinfectant solution prepared in the dilution tank (300); e) When the free chlorine content measured in step d) reaches the expected free chlorine content value of the disinfectant solution, interrupt the electrolysis; f) Optionally, measure the free chlorine content of the disinfectant solution prepared in the dilution tank through the sensor (411); g) Optionally, perform the operation of interrupting the electrolysis in step e) through the control unit (600). The control unit is used to compare the free chlorine content measured by the sensor (411) in step f) with the free chlorine content threshold, and interrupt the electrolysis when the free chlorine content measured by the sensor (411) is equal to or higher than the free chlorine content threshold; h) Optionally, measure at least one inherent parameter of the disinfectant solution prepared in the dilution tank (300), and the inherent parameter is selected from the list of pH value, temperature, conductivity and hardness parameters; i) Optionally, adjust the pH value of the disinfectant solution prepared in the dilution tank (300).

21. The method according to claim 20, characterized in that, In step c), the range of the voltage applied to the electrodes is between 1 volt and 15 volts, preferably between 2 volts and 10 volts.

22. The method according to claim 20 or 21, characterized in that, The pH value range of the hypochlorous acid disinfectant solution is about 5.1 to 6.9, preferably the pH value is about 6.

5.

23. The method according to any one of claims 19 to 21, characterized in that, In the optional step g), the free chlorine content threshold is set to the maximum value selected from the range of 5 ppm to 3000 ppm, especially the range of 10 ppm to 1500 ppm.

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